Successful device detection and the assigned device.

The necessary Linux driver to access USB BitScopes is included as standard with the kernel in all modern distributions. If you want to check the kernel has created a device for BitScope when you plug it in, run the following command (as root) and then plug in your USB BitScope. You should see output like this:

The important line is the last one reporting ttyUSB0 (or ttyUSB<N> where N is some other number). This is the device (i.e. /dev/ttyUSB<N>) to use to connect with BitScope. Note: there may be other lines reported as other daemons on your system (like mtp-probe) probe the new device to see if it belongs to them. You can ignore these.

Check the USB Driver exists on your system.

If nothing happens when you plug in your BitScope the driver may not be installed. This is very rare these days but you can check (while BitScope is plugged in) with the following command:

If these three modules (ftdi_sio, usbserial and usbcore) are not loaded on your system you may need to upgrade your kernel or configure your system to install the ftdi_sio driver. See the driver home page for full details.

Choose the correct serial port (if not already selected).

If you have only one BitScope connected and there are no other USB serial devices connected to your PC, this step should be unecessary.

Otherwise, you may need to select the correct serial port manually using BitScope DSO (or any other BitScope software application) to choose which of several devices is the correct one.

The SETUP dialog shown here is how you do this.

The drop-down list shows usb serial devices that may be selected or you can simply type in the name of the device if you know what it is. Note that the list of options may be shorted shown.

If there is only one device connected, it will be the only one shown in the list and it will probably have been automatically pre-selected.

there is a conflict, in this case with the brltty package per the last three lines of this log excerpt. In our view it's incorrect that any package preemptively claims ownership of a generic serial device so we recommend removing the offending package if you don't need it.

Check you have permission to access the device.

With some distributions you may need to add your user to the dialout group if this is not done automatically. This applies to some recent linux distributions including Ubuntu which have changed the permissions for ordinary users (i.e. only the adminstrator user has access by default).

Assuming your BitScope appears at /dev/ttyUSB0 you can check the permissions from a terminal as follows:

That is, the group permissions should be dialout. Check your login permissions include dialout, type:

$ groups

If dialout is not listed you will need to add it to your login which can be done at the command line as:

$ sudo adduser $USER dialout

where $USER is your user name. You will then need to logout and login again (for the new group to apply) and you should be good to go.

Check there are no stale lock files.

The lock file is a mechanism that restricts access to BitScope to one application at a time. The lock file is created by the app when the app starts and deleted when it terminates. If an app terminates abnormally or is manually killed the lock file may remain in place preventing further access to the device. You can check this as follows:

root@fermi:~#ls /var/lock
LCK..ttyUSB0

In this case the /dev/ttyUSB0 device is locked. Simply delete this file if it exists (when no application has the device open). Note: if you want to share one USB BitScope between multiple applications, or even multiple users on different computers you can; see BitScope Server for details.

If you still have problems, especially if you are upgrading from older software versions, the configuration files used by the application software may have been corrupted. The file most likely to cause problems (if corrupt) is the probe file.

The local probe file is located at:

~/.config/bitscope/bitscope.prb

Delete this file to force the software to recreate it with correct information.

This is unlikely to be corrupt but if you suspect it is, and you have adminstrator privileges on your PC to modify it, you can delete (or comment out) its contents (don't delete the file itself). It is highly unlikely you will need to do this but we mention it here as a last resort.